The Blog

A library of stories and sources

From early cities and scripts to beliefs, science, and contested history. Pick a subject, read a guide, and open the material behind it.

Every guide links its sources. We mark what comes from a surviving object, what belongs to a tradition, and what remains a hypothesis.

7 of 96 source guides

Southwest Amazonia, Brazil Precolonial landscape; modeled peak around 100–300 CE

Amazon earthworks: 432 observed, thousands estimated

A laser survey found 432 earthworks. The thousands more in the headline are a model estimate, not newly observed sites.

Mesopotamia 1000–500 BCE

MUL.APIN: a Babylonian compendium of the sky

The MUL.APIN tablet preserves Babylonian knowledge of the sky. The surviving copy’s date does not tell us when that tradition began.

Babylon 652–651 BCE

Astronomical Diaries: a dated record of the Babylonian sky

Babylonian scribes left dated observations of the sky. Tablet BM 32312 helps separate a recorded event from a later explanation of it.

Alexandria, Baghdad, Toledo, Saragossa 2nd century CE – 1381 CE

The Almagest: one book, four cities, a thousand years

Ptolemy’s astronomy moved through Arabic and Latin translations. A manuscript from Zaragoza marks one stop on a journey spanning more than a thousand years.

Cracow, Padua, and Uppsala 14th–16th centuries CE

Bianchini’s tables in Copernicus’s hand: what is proven?

Copernicus copied planetary latitude tables in his own hand. It is a strong find, but does not by itself settle every question about how he used them.

Maragha, Constantinople, and the Italian Renaissance 13th–16th centuries CE

The Tusi couple in Greek: why a shared error matters

A Greek text preserves a Persian Moon model and repeats a numerical error. That shared mistake is stronger evidence of a textual link than a similar drawing.

Damascus and Oxford c. 1366 CE and after

Ibn al-Shatir: which manuscript preserves the relevant theory?

His fourteenth-century planetary theory survives in several manuscripts. His separate work on the astrolabe does not alone prove that his Mercury model reached Copernicus.